1. Field of the Invention
The present invention relates to surge suppressers or more particularly to replaceable surge protector assemblies for telephone network interfaces.
2. Description of the Prior Art
Telephone network interface devices are well known in the art. Such equipment connects telephone company wiring to wiring serving individual telephone subscribers. Typical telephone network interface devices are described in U.S. Pat. Nos. 5,570,422; 5,416,837; 5,497,416; 5,479,505; and 5,333,193. The telephone network interface devices typically comprises a plurality of terminals in arranged in an array for connecting to several incoming telephone lines from a telephone company. These lines are then connected to complementary wiring in a house or office via the interface. In the usual case, the terminals are protected with a surge suppresser for grounding unexpected current surges. Such cause a short circuit to ground for a current overload condition which may be caused by a lightning strike. The interface changes from a first state which allows normal telephone current to proceed through the interface to a second state during an electrical surge condition. Normally a short circuit to ground is created during a surge to protect electrical components from damage. Protected telephone network interface devices are known from U.S. Pat. Nos. 5,3313,519; 5,438,619; 5,557,065; 5,548,641 and 5,373,413.
A key problem with prior art surge suppressers is that they are only useful for a single lightning hit. Once lightning hits, the telephone network interface device is expended and must be entirely replaced This may cause an outage in telephone service for a considerable length of time. The principal reason interfaces are expended is because gas filled surge suppressing elements are hard wired to the interface device. In addition, due to their very small size, handling such elements has been difficult. It would be desirable to provide a telephone network interface device which has pluggable, surge suppressing elements which are easily replaceable in an interface which has been hit by lightning. In this way repair is simplified, expedited and much less costly. While replaceable, pluggable surge suppressers are known for other applications, such are inconvenient for telephone interface applications due to restrictive space requirements and handling difficulties.
The present invention provides a holder which both protects the surge suppressing elements and makes them easier to handle.